CIFS: Simplify invalidate part (try #5)

Simplify many places when we call cifs_revalidate/invalidate to make
it do what it exactly needs.

Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>

4 files changed, 113 insertions, 57 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index f736d8a2e771..0f6a54f14eff 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -618,16 +618,29 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int origin)
 {
         /* origin == SEEK_END => we must revalidate the cached file length */
         if (origin == SEEK_END) {
-                int retval;
-
-                /* some applications poll for the file length in this strange
-                   way so we must seek to end on non-oplocked files by
-                   setting the revalidate time to zero */
-                CIFS_I(file->f_path.dentry->d_inode)->time = 0;
-
-                retval = cifs_revalidate_file(file);
-                if (retval < 0)
-                        return (loff_t)retval;
+                int rc;
+                struct inode *inode = file->f_path.dentry->d_inode;
+
+                /*
+                 * We need to be sure that all dirty pages are written and the
+                 * server has the newest file length.
+                 */
+                if (!CIFS_I(inode)->clientCanCacheRead && inode->i_mapping &&
+                    inode->i_mapping->nrpages != 0) {
+                        rc = filemap_fdatawait(inode->i_mapping);
+                        mapping_set_error(inode->i_mapping, rc);
+                        return rc;
+                }
+                /*
+                 * Some applications poll for the file length in this strange
+                 * way so we must seek to end on non-oplocked files by
+                 * setting the revalidate time to zero.
+                 */
+                CIFS_I(inode)->time = 0;
+
+                rc = cifs_revalidate_file_attr(file);
+                if (rc < 0)
+                        return (loff_t)rc;
         }
         return generic_file_llseek_unlocked(file, offset, origin);
 }
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index bb64313fd750..d304584408d1 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -59,9 +59,11 @@ extern int cifs_mkdir(struct inode *, struct dentry *, int);
 extern int cifs_rmdir(struct inode *, struct dentry *);
 extern int cifs_rename(struct inode *, struct dentry *, struct inode *,
                        struct dentry *);
+extern int cifs_revalidate_file_attr(struct file *filp);
+extern int cifs_revalidate_dentry_attr(struct dentry *);
 extern int cifs_revalidate_file(struct file *filp);
 extern int cifs_revalidate_dentry(struct dentry *);
-extern void cifs_invalidate_mapping(struct inode *inode);
+extern int cifs_invalidate_mapping(struct inode *inode);
 extern int cifs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 extern int cifs_setattr(struct dentry *, struct iattr *);
 
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0aeaaf7bf153..c672afef0c09 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1445,8 +1445,13 @@ int cifs_strict_fsync(struct file *file, int datasync)
         cFYI(1, "Sync file - name: %s datasync: 0x%x",
                 file->f_path.dentry->d_name.name, datasync);
 
-        if (!CIFS_I(inode)->clientCanCacheRead)
-                cifs_invalidate_mapping(inode);
+        if (!CIFS_I(inode)->clientCanCacheRead) {
+                rc = cifs_invalidate_mapping(inode);
+                if (rc) {
+                        cFYI(1, "rc: %d during invalidate phase", rc);
+                        rc = 0; /* don't care about it in fsync */
+                }
+        }
 
         tcon = tlink_tcon(smbfile->tlink);
         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
@@ -1903,8 +1908,11 @@ int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
 
         xid = GetXid();
 
-        if (!CIFS_I(inode)->clientCanCacheRead)
-                cifs_invalidate_mapping(inode);
+        if (!CIFS_I(inode)->clientCanCacheRead) {
+                rc = cifs_invalidate_mapping(inode);
+                if (rc)
+                        return rc;
+        }
 
         rc = generic_file_mmap(file, vma);
         if (rc == 0)
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index fbe7d5858563..0cc7eddb077f 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1683,18 +1683,15 @@ cifs_inode_needs_reval(struct inode *inode)
 /*
  * Zap the cache. Called when invalid_mapping flag is set.
  */
-void
+int
 cifs_invalidate_mapping(struct inode *inode)
 {
-        int rc;
+        int rc = 0;
         struct cifsInodeInfo *cifs_i = CIFS_I(inode);
 
         cifs_i->invalid_mapping = false;
 
         if (inode->i_mapping && inode->i_mapping->nrpages != 0) {
-                /* write back any cached data */
-                rc = filemap_write_and_wait(inode->i_mapping);
-                mapping_set_error(inode->i_mapping, rc);
                 rc = invalidate_inode_pages2(inode->i_mapping);
                 if (rc) {
                         cERROR(1, "%s: could not invalidate inode %p", __func__,
@@ -1704,56 +1701,52 @@ cifs_invalidate_mapping(struct inode *inode)
         }
 
         cifs_fscache_reset_inode_cookie(inode);
+        return rc;
 }
 
-int cifs_revalidate_file(struct file *filp)
+int cifs_revalidate_file_attr(struct file *filp)
 {
         int rc = 0;
         struct inode *inode = filp->f_path.dentry->d_inode;
         struct cifsFileInfo *cfile = (struct cifsFileInfo *) filp->private_data;
 
         if (!cifs_inode_needs_reval(inode))
-                goto check_inval;
+                return rc;
 
         if (tlink_tcon(cfile->tlink)->unix_ext)
                 rc = cifs_get_file_info_unix(filp);
         else
                 rc = cifs_get_file_info(filp);
 
-check_inval:
-        if (CIFS_I(inode)->invalid_mapping)
-                cifs_invalidate_mapping(inode);
-
         return rc;
 }
 
-/* revalidate a dentry's inode attributes */
-int cifs_revalidate_dentry(struct dentry *dentry)
+int cifs_revalidate_dentry_attr(struct dentry *dentry)
 {
         int xid;
         int rc = 0;
-        char *full_path = NULL;
         struct inode *inode = dentry->d_inode;
         struct super_block *sb = dentry->d_sb;
+        char *full_path = NULL;
 
         if (inode == NULL)
                 return -ENOENT;
 
-        xid = GetXid();
-
         if (!cifs_inode_needs_reval(inode))
-                goto check_inval;
+                return rc;
+
+        xid = GetXid();
 
         /* can not safely grab the rename sem here if rename calls revalidate
            since that would deadlock */
         full_path = build_path_from_dentry(dentry);
         if (full_path == NULL) {
                 rc = -ENOMEM;
-                goto check_inval;
+                goto out;
         }
 
-        cFYI(1, "Revalidate: %s inode 0x%p count %d dentry: 0x%p d_time %ld "
-                 "jiffies %ld", full_path, inode, inode->i_count.counter,
+        cFYI(1, "Update attributes: %s inode 0x%p count %d dentry: 0x%p d_time "
+                 "%ld jiffies %ld", full_path, inode, inode->i_count.counter,
                  dentry, dentry->d_time, jiffies);
 
         if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)
@@ -1762,41 +1755,81 @@ int cifs_revalidate_dentry(struct dentry *dentry)
                 rc = cifs_get_inode_info(&inode, full_path, NULL, sb,
                                          xid, NULL);
 
-check_inval:
-        if (CIFS_I(inode)->invalid_mapping)
-                cifs_invalidate_mapping(inode);
-
+out:
         kfree(full_path);
         FreeXid(xid);
         return rc;
 }
 
+int cifs_revalidate_file(struct file *filp)
+{
+        int rc;
+        struct inode *inode = filp->f_path.dentry->d_inode;
+
+        rc = cifs_revalidate_file_attr(filp);
+        if (rc)
+                return rc;
+
+        if (CIFS_I(inode)->invalid_mapping)
+                rc = cifs_invalidate_mapping(inode);
+        return rc;
+}
+
+/* revalidate a dentry's inode attributes */
+int cifs_revalidate_dentry(struct dentry *dentry)
+{
+        int rc;
+        struct inode *inode = dentry->d_inode;
+
+        rc = cifs_revalidate_dentry_attr(dentry);
+        if (rc)
+                return rc;
+
+        if (CIFS_I(inode)->invalid_mapping)
+                rc = cifs_invalidate_mapping(inode);
+        return rc;
+}
+
 int cifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
                  struct kstat *stat)
 {
         struct cifs_sb_info *cifs_sb = CIFS_SB(dentry->d_sb);
         struct cifsTconInfo *tcon = cifs_sb_master_tcon(cifs_sb);
-        int err = cifs_revalidate_dentry(dentry);
+        struct inode *inode = dentry->d_inode;
+        int rc;
 
-        if (!err) {
-                generic_fillattr(dentry->d_inode, stat);
-                stat->blksize = CIFS_MAX_MSGSIZE;
-                stat->ino = CIFS_I(dentry->d_inode)->uniqueid;
+        /*
+         * We need to be sure that all dirty pages are written and the server
+         * has actual ctime, mtime and file length.
+         */
+        if (!CIFS_I(inode)->clientCanCacheRead && inode->i_mapping &&
+            inode->i_mapping->nrpages != 0) {
+                rc = filemap_fdatawait(inode->i_mapping);
+                mapping_set_error(inode->i_mapping, rc);
+                return rc;
+        }
 
-                /*
-                 * If on a multiuser mount without unix extensions, and the
-                 * admin hasn't overridden them, set the ownership to the
-                 * fsuid/fsgid of the current process.
-                 */
-                if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER) &&
-                    !tcon->unix_ext) {
-                        if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID))
-                                stat->uid = current_fsuid();
-                        if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID))
-                                stat->gid = current_fsgid();
-                }
+        rc = cifs_revalidate_dentry_attr(dentry);
+        if (rc)
+                return rc;
+
+        generic_fillattr(inode, stat);
+        stat->blksize = CIFS_MAX_MSGSIZE;
+        stat->ino = CIFS_I(inode)->uniqueid;
+
+        /*
+         * If on a multiuser mount without unix extensions, and the admin hasn't
+         * overridden them, set the ownership to the fsuid/fsgid of the current
+         * process.
+         */
+        if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER) &&
+            !tcon->unix_ext) {
+                if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID))
+                        stat->uid = current_fsuid();
+                if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID))
+                        stat->gid = current_fsgid();
         }
-        return err;
+        return rc;
 }
 
 static int cifs_truncate_page(struct address_space *mapping, loff_t from)